AIM: To investigate the effects of phorbol ester (TPA) on the anti-tumor effect and renal toxicity of cisplatin (CP).  METHODS: MTT assay was used to examine the effect of TPA on the proliferation inhibition of CP in A549 and SPC-A-1 lung cancer cells. Also the effect of TPA on acute toxicity of CP was observed by once injection of high dose CP through caudal vein; The tumor-bearing mice model was explored to investigate the effect of TPA on tumor inhibition ratio and renal toxicity of CP in vivo. And the effect of TPA on renal oxidative stress induced by CP was detected. RESULTS: 1 ng/mL TPA could significantly enhance the inhibitory effect of CP on cell proliferation. In acute toxicity test, TPA could significantly reduce the toxicity of CP and prolong the survival time of animals. And the tumor weight (P<0.05), serum creatinine (P<0.05) and urea nitrogen levels (P<0.01) in TPA combined with CP group were significantly lower than those in CP group. Meanwhile, the results of HE staining showed that the renal tissue damage was significantly reduced in the combined group compared with CP group. The contents of MDA in renal tissue were decreased (P<0.01). However, the contents of GSH and the activity of SOD were increased (P<0.05) in TPA and CP combined group. CONCLUSION: TPA can enhance the inhibitory effect of CP on cell proliferation and inhibit tumor growth in tumor-bearing mice. At the same time, TPA can reduce the renal toxicity of CP, which may be related to the inhibition of renal oxidative stress induced by CP.